Optimizing a 460ci stroker
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From: VA
If he would have shifted gears at 5250 it would have went in the 10s........good lord that thing is 1960s big block rpm curve.
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From: Coast of San Mateo County Between Pacifica & HMB
Thread Starter
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From: Chicago, IL
Ideally he and the tuner would log a drag pass and see what the converter is flashing too and then also look at the RPM drop on the shift to figure out where to shift it.
Curious on the prior comment about bigbaddy picking up from a runner change.
Last edited by Pro Stock John; Sep 20, 2021 at 05:08 PM.
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I dont think this is a case of replacing parts first. Yeah, going to a bigger throttle body would help top end, but the torque curve is mad.
My first thought is torque converter ghosting the torque number way up, and the final power number down, which is what doing chassis dyno pulls with the torque converter unlocked does, and may be flashing the torque converter at the top of the pull, depressing top end torque numbers even further. Even if the torque converter was locked, if you don't have enough pressure or something else is bad you can spin the lockup clutch. The raw data without torque smoothing may show something interesting.
If its real, and not a fudged graph, first thing to check would be the position of the cam, because making that much torque that low with that big of a cam it looks like it is installed WAY advanced. Like put the crank sprocket on backwards, 10+ degrees advanced.
With that cam you could put a set of untouched factory LS3 heads and intake on this engine, and make more power than the graph shows.
My first thought is torque converter ghosting the torque number way up, and the final power number down, which is what doing chassis dyno pulls with the torque converter unlocked does, and may be flashing the torque converter at the top of the pull, depressing top end torque numbers even further. Even if the torque converter was locked, if you don't have enough pressure or something else is bad you can spin the lockup clutch. The raw data without torque smoothing may show something interesting.
If its real, and not a fudged graph, first thing to check would be the position of the cam, because making that much torque that low with that big of a cam it looks like it is installed WAY advanced. Like put the crank sprocket on backwards, 10+ degrees advanced.
With that cam you could put a set of untouched factory LS3 heads and intake on this engine, and make more power than the graph shows.
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Last edited by BigDaddy97; Sep 20, 2021 at 06:25 PM.
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103 throttle body installed and adjusted. car feels way better but it's hard to know for sure until I get to the track. weather has been terrible DA has been especially high recently. Also I'm waiting on a 5" air intake tube and filter, but it seems ok with the 4" for now.
Staging Lane
Joined: Jun 2013
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Got a buddy with a 460 ci stroker:
I'm thinking he should move to a 102 TB and a bigger air intake tube, 4" or maybe he can try doing something over the radiator, not sure what fits.
Any suggestions or comments? I also suggested he figure out compression in case it's up there and maybe he can do flex fuel E85 setup.
- Ported LS3 heads
- 4.250 stroke engine
- 242/256 114 cam
- FAST 102 intake
- 1 7/8 headers, 3" exhaust
- stock DBW TB
- 3.5 air intake
- 4L80E
- pump gas
I'm thinking he should move to a 102 TB and a bigger air intake tube, 4" or maybe he can try doing something over the radiator, not sure what fits.
Any suggestions or comments? I also suggested he figure out compression in case it's up there and maybe he can do flex fuel E85 setup.
John,
I really like the oem LS3 heads for budget builds but I have never seen a hyd roller plastic manifold LS3 with any form of oem heads even make 600 rwhp.
Sometimes or should I say we often see 75+ RWHP gains changing to LS7 heads and the MSD LS7 manifold from even ported LS3 stuff FWIW.
The LS7 architecture just destroys all the other ones pretty bad especially the larger the engine gets. Then your problem becomes the small TBs those plastic manifolds use.
With the bigger LS7 intakes like the hi-ram and CID your gains start going from 650+ to 725+ and even higher with 108mm+ TBs and with solid rollers or more compression of course.
The CID sets the tq you can or will make for the most part and the heads and intake set what total power you will make ultimately.
Not that any of that is exactly groundbreaking information or anything.
Thread Starter
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From: Chicago, IL
Staging Lane
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@Brer Rabbit check out Erik's post, he has been building LS engines for gotta be over 20 years now.
It just sucks that we have to have hoods! Of course LME and Frankenstein etc. have some really nice short runner billet stuff too for extremely high rpm stuff or power adders and they will fit under the hood.
They are just kind pricy for us poor people but also do look really nice!
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Thanks John! Everyone has had good advice on here but the heads and intake and TB are what it takes to keep the power going up higher in rpm and with the larger engines it's even more of a gain.
It just sucks that we have to have hoods! Of course LME and Frankenstein etc. have some really nice short runner billet stuff too for extremely high rpm stuff or power adders and they will fit under the hood.
They are just kind pricy for us poor people but also do look really nice!
It just sucks that we have to have hoods! Of course LME and Frankenstein etc. have some really nice short runner billet stuff too for extremely high rpm stuff or power adders and they will fit under the hood.
They are just kind pricy for us poor people but also do look really nice!
